1 /* 2 * Copyright (c) 2018-2022, ARM Limited and Contributors. All rights reserved. 3 * 4 * SPDX-License-Identifier: BSD-3-Clause 5 */ 6 7 /* Helper functions to offer easier navigation of Device Tree Blob */ 8 9 #ifndef FDT_WRAPPERS_H 10 #define FDT_WRAPPERS_H 11 12 #include <libfdt_env.h> 13 14 /* Number of cells, given total length in bytes. Each cell is 4 bytes long */ 15 #define NCELLS(len) ((len) / 4U) 16 17 int fdt_read_uint32(const void *dtb, int node, const char *prop_name, 18 uint32_t *value); 19 uint32_t fdt_read_uint32_default(const void *dtb, int node, 20 const char *prop_name, uint32_t dflt_value); 21 int fdt_read_uint64(const void *dtb, int node, const char *prop_name, 22 uint64_t *value); 23 int fdt_read_uint32_array(const void *dtb, int node, const char *prop_name, 24 unsigned int cells, uint32_t *value); 25 int fdtw_read_string(const void *dtb, int node, const char *prop, 26 char *str, size_t size); 27 int fdtw_read_uuid(const void *dtb, int node, const char *prop, 28 unsigned int length, uint8_t *uuid); 29 int fdtw_write_inplace_cells(void *dtb, int node, const char *prop, 30 unsigned int cells, void *value); 31 int fdtw_read_bytes(const void *dtb, int node, const char *prop, 32 unsigned int length, void *value); 33 int fdtw_write_inplace_bytes(void *dtb, int node, const char *prop, 34 unsigned int length, const void *data); 35 int fdt_get_reg_props_by_index(const void *dtb, int node, int index, 36 uintptr_t *base, size_t *size); 37 int fdt_get_reg_props_by_name(const void *dtb, int node, const char *name, 38 uintptr_t *base, size_t *size); 39 int fdt_get_stdout_node_offset(const void *dtb); 40 41 uint64_t fdtw_translate_address(const void *dtb, int bus_node, 42 uint64_t base_address); 43 44 int fdtw_for_each_cpu(const void *fdt, 45 int (*callback)(const void *dtb, int node, uintptr_t mpidr)); 46 47 int fdtw_find_or_add_subnode(void *fdt, int parentoffset, const char *name); 48 49 static inline uint32_t fdt_blob_size(const void *dtb) 50 { 51 const uint32_t *dtb_header = dtb; 52 53 return fdt32_to_cpu(dtb_header[1]); 54 } 55 56 #define fdt_for_each_compatible_node(dtb, node, compatible_str) \ 57 for (node = fdt_node_offset_by_compatible(dtb, -1, compatible_str); \ 58 node >= 0; \ 59 node = fdt_node_offset_by_compatible(dtb, node, compatible_str)) 60 61 #endif /* FDT_WRAPPERS_H */ 62